KR100341803B1 - Integral head system for improving signal-to-noise rate - Google Patents

Abstract

PURPOSE: An integral head system for improving signal-to-noise rate is provided to remove various noise contained in the data read by a head, thereby improving the signal-to-noise rate of the read signal amplified and output from an amplifier. CONSTITUTION: An integral head system for improving signal-to-noise rate includes a head(12) mounted to a head slider body of a hard disc drive for reading write data, a low pass filter mounted to the head slider body for removing noise from the signal generated by the head, a programming filter mounted to the head slider body for optimizing the signal output from the low pass filter, and an amplifier(16) for amplifying the read signal output from the programming filter.

Description

Integrated head unit to improve signal-to-noise ratio

The present invention relates to a hard disk drive, and more particularly, to a head device for improving a signal to noise ratio (S / N ratio).

In general, a hard disk drive includes a head for writing or reading data recorded on a magnetic disk. When driving the hard disk drive, the head will fly on the track on the magnetic disk while maintaining a constant flight altitude. At this time, the actuator moves the head radially on the disk during the track search, and fixes the head on the track during the track following. Typically, disks of a hard disk drive using a multi-platter method are installed in one spindle, and each disk surface corresponds to one head. Thus all heads are moved together by the movement of the actuator.

1 shows a schematic block diagram of a general hard disk drive. The magnetic disk 10, which is a recording medium, is rotated by the spindle motor 32. As shown in FIG. The heads 12 are located on the surface of one disk 10 corresponding to the disk module 10 and are mounted on a vertically extending support arm 14 of the arm assembly of the actuator 28. The preamplifier 16 preamplifies the signal picked up by the head 12 during data read and applies the analog read signal to the read / write channel circuit 18. Encoded write data applied from the read / write channel 18 circuit is written onto the magnetic disk 10 via a corresponding one of the heads 12. The read / write channel 18 circuit detects and decodes a data pulse from a read signal applied from the preamplifier 16 and applies it to a DDC (Disk Bata Controller) (DDC) 20, which is applied from the DDC 20. The write data is encoded and applied to the preamplifier 16. The DDC 20 is controlled by the microcontroller 24 and writes data received from the host computer to or reads from the disk 10 through the read / write channel 18 circuit and the pre-weight portion 16. Send data to the host computer. The DDC 20 also interfaces the communication between the host computer and the microcontroller 24. The microcontroller 24 controls the DDC 20 in response to a read or write command received from the host computer and controls track search and track following. The servo driver 26 generates a driving current for driving the actuator 28 by a signal for position control of the heads 12 generated from the microcontroller 24 to generate a voice coil of the actuator 28. ) Is applied. The actuator 28 moves the heads 12 on the disks 10 in correspondence with the direction and level of the driving current applied from the servo driver 26. The spindle motor driver 30 rotates the disks 10 by driving the spindle motor 32 in accordance with a control value for the rotation control of the disks 10 generated from the microcontroller 24. The disk signal controller 22 generates various timing signals necessary for read / write, decodes the servo information, and applies it to the microcontroller 24. In the conventional hard disk drive having the above-described configuration, the preamplifier 16 is integrated with a read / write channel circuit 18 in one integrated circuit chip (IC Chip). An example of such a chip is the SSI 32R2210R, a thin film lead / write device from Silicon Systems. The read / write channel circuit 18 is largely divided into a head switching circuit, a read buffer and a write circuit, and the head switching circuit selects a specific head among a plurality of heads by a signal applied from the DDC 20. Each of the read buffer and the write circuit is a circuit for buffering a signal read from the head selected by the head switching circuit or applying a current corresponding to the write signal applied from the DDC 20 to the specific head. Meanwhile, the preamplifier 16 is connected between the head switching circuit and the read / write circuit. In the hard disk drive having the above-described configuration, the signal read by the head 12 in accordance with the magnetic change on the magnetic disk 10 is very weak. Therefore, the pre-amplifier 16 amplifies the signal read from the head 12 and outputs the read / write channel circuit 18. However, the signal amplified by the preamplifier 16 includes various noises. For example, the noise inside the head, the electrical resistance on the lead signal transmission path, the variability of the preamplifier 16, the external noise from the preamplifier 16 at the output terminal of the head 12, and the like. Amplified together with the read signal is input to the read / write channel circuit 18. Therefore, a large amount of noise is introduced into the signal read from the head 12, and thus the signal-to-noise ratio is gradually lowered, thereby degrading the reliability of the hard disk drive.

Accordingly, an object of the present invention is to provide an integrated head device capable of improving the signal-to-noise ratio by optimizing the noise included in the read signal during the data read operation of the hard disk drive.

The present invention for achieving the above object is an integrated head device for improving the signal-to-noise ratio of the hard disk drive,

A head mounted on the head slider node of the hard disk drive to read write data;

Filtering means mounted on the head slider body to remove noise of a signal generated from the head;

Programming filtering means mounted on the head slider body to optimize a signal output from the filtering means;

Amplifying means for amplifying and outputting the signal output from the programming filtering means.

Hereinafter, exemplary operations of the present invention will be described in detail with reference to the accompanying drawings. In the following description, it should be noted that like elements in the drawings represent like reference numerals wherever possible. Also in the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention, such as specific head and slider configurations. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

2 is a block diagram of the head device 40 for improving the signal-to-noise ratio according to the present invention. The head device 40 includes a head 12 for reading and writing data on the magnetic disk 10. And a low pass filter (LPF) 36 for filtering the noise contained in the signal read from the head 12 before amplification, and programming for optimizing the read signal filtered through the LPF 36. The filter 38 and the read signal preamplifier 16 amplify the read signal optimized through the programming filter 38. Referring to FIG. 2, when there is a data read command from the host computer, signals read from the head 12 are applied to the LPF 36 through conductive lines, respectively. LPF 36, which is connected between the head 12 and the lead signal preamplifier 16, performs low pass filtering of the signal read from the head 12, so that only signals in a desired frequency band can be programmed through the conductive line. 38). The filtered read signal is then amplified by the read signal preamplifier 16 and applied to the read buffer 42 after intrinsic noise of the head 12 and noise during reproduction of the light signal are optimized through the programming filter 38. . That is, by connecting the LPF 36 and the programming filter 38 between the head 12 and the lead signal preamplifier 16, various external noises included in the signal read out from the head 12 and the head 12 are included. Intrinsic noise can be minimized. Hereinafter, a process of forming the head 12, the LPF 36, the programming filter 38, and the read signal preamplifier 16 described above with reference to FIG. 3 on one head slider will be described. do. The head slider means a main body to which a head can be attached, and the head and the head slider are usually named together in some cases. In the following description, the sensor 46 and the gold pad 48, which are the core of the head 12, constitute the head 12, and the head 12 is combined with the slider body. Define as configuring the head slider.

3 shows a head apparatus for explaining a process of forming the head 12, the LPF 36, the programming filter 38, and the read signal preamplifier 16 in one slider body 44 by a semiconductor process. 40 shows a perspective view. 3A is a perspective view of the slider body 44 made by the semiconductor process, and the ABS (Air Bearing Surface) of the slider body 44 is determined according to the model type. In this case, the slider body 44 is designed to be equipped with the LPF 36, the programming filter 38, and the read signal preamplifier 16 using the semiconductor manufacturing technology. On the other hand (3b) is a perspective view of the head 12 made by the wafer process, the head 12 is a thin film head and a sensor 44 for detecting a change in the magnetic signal read from the magnetic disk 10 and It consists of a gold pad 46. (3c) shows a perspective view of the head slider provided with the head device 40 according to the present invention. The slider body 44 of 3a and the head 12 of 3b are combined. At this time, the input terminal of the LPF 36 mounted in the slider body 44 and the gold pad 46 of the head 12 are connected by a magnet wire. Accordingly, the signal read from the sensor 46 of the head 12 flying on the magnetic disk 10 at a certain height is input to the LPF 36 in the slider body 44. As a result, noise generated by external factors such as the head 12 and the magnetic disk 10 is filtered and optimized by the LPF 36 and the programming filter 38, respectively, so that only the pure read signal is the read signal preamplifier 16. ) Is output to the read buffer 42 through.

As described above, the present invention can minimize the noise included in the read signal by filtering and optimizing the signal read from the head, thereby improving the signal-to-noise ratio of the read signal amplified and output through the read signal preamplifier. There is an advantage.

1 is a schematic block diagram of a general hard disk drive.

2 is a block diagram of an integrated head device 40 according to the present invention.

3 is a perspective view of the head device 40 according to the present invention.

Claims (4)

In the integrated head device for improving the signal-to-noise ratio of the hard disk drive, A head mounted to a head slider body of the hard disk drive to lead a light data; Filtering means mounted to the head slider body to filter and output a signal generated from the head; Control mounted on the head slider body and programmable filtering means for optimizing noise included in a signal output from the filtering means; And amplifying means mounted on the head slider body and configured to amplify and output the read signal output from the programming filtering means. The integrated head device of claim 1, wherein the head is a thin film head. 3. The integrated head device according to claim 2, wherein the filtering means, the programming filtering means and the amplifying means are mounted in the head slider body by a semiconductor manufacturing process. 4. The integrated head device according to claim 3, wherein said filtering means is a low pass filter.